Add a few more paths to gitignore

Howdy!

This app is awesome, thanks for all the hard work on it! I've been taking a look and am interested in adding a few more radio stations, but wanted to see if a change like this was the kind of thing y'all are open to. If I run git status I've still got some files remaining, so I'm happy to add these paths too (but they could be special cases, and didn't want to assume):

data/Makefile
data/gnome-internet-radio-locator.appdata.xml
data/gnome-internet-radio-locator.desktop
data/icons/1024x1024/Makefile
data/icons/16x16/Makefile
data/icons/22x22/Makefile
data/icons/24x24/Makefile
data/icons/256x256/Makefile
data/icons/32x32/Makefile
data/icons/48x48/Makefile
data/icons/512x512/Makefile
data/icons/Makefile
gnome-internet-radio-locator.spec
help/C/version.xml
help/Makefile
m4/libtool.m4
man/Makefile
po/.intltool-merge-cache.lock
po/Makefile.in.in
src/Makefile